I know very little about how open source projects work and how devs choose the features they work on, but would a bounty system be worth the headache? Maybe someone knows of a tool or website that allows communities to suggest and pledge money towards desired features? I think that would avoid a lot of pitfalls. If what you're asking is how to use funds managed by the association, maybe the various elected councilors could receive a budget to manage take on the task of assigning bounties for things they'd like devs to focus on. 50 bucks will obviously not mean much to seasoned devs doing this on the side, but it might attract hobbyists or beginners, that, under the guidance of our senior devs, could help with the less glamorous aspects.
And since the thread has somehow also become about marketing vs player retention, I'd like to mention 2 great features, one still in need of some polish, the other only a suggestion for now, that could help with the latter:
The league system was a move in the right direction to emphasize ladder more over custom games, and the system is in place, the icons are very nice, but we don't use them enough in the client and ingame right now. The client UI needs to be checked meticulously and modified such that every instance where a player is mentioned and their global rating displayed is modified to emphasize league first and foremost. Those league icons should be like the country flag, always attached to the nickname, only then will the true potential of the league system be within reach, that is, shifting the culture away from custom games and global rating.
Another proposal I thought was very very promising (apologies, I forget who suggested it) was a chat wheel ingame. Managing toxicity in competitive team games is partly about removing sources of frustration, and a good, formalized, useful and fast communication tool does just that. Something to bridge the gap between the fast but vague ping and the tedious, unreliable (because of language barriers) and potentially insulting team chat. Even the basic pings could be improved upon if they showed an arrow towards the location when you're too zoomed in to see them. As they are now, a new player might not even realize what the sounds are about and miss them completely.